Breaking the dormancy of niagara rosada seeds without stratificationThe objective of this study was to asses the effect of three factors on the germination of grape seeds, cv. Niagara Rosada. The three studied factors were: physical treatments, chemical treatments and germination environment. The physical treatments consisted of whole seeds, seeds with a cross cut in the median region and seeds with a cut in the micropyle. The chemical treatments were applied by immersing whole seeds in aqueous solution of gibberellic acid (GA 3 ) with concentrations of 0 and 4000 mg L -1 . The environments evaluated were in vitro and ex vitro. The experiment was arranged in a factorial 3 x 2x 2, randomized blocks design, with 4 repetitions, each one consisting of a Gerbox® containing 25 seeds or a rack with 25 test tubes. The parameters evaluated were the percentage and speed of seed germination. The results showed that cutting is essential to the germination of non-stratified seeds. The combination micropyle cut, 4000 mg L -1 of GA 3 and in vitro environment resulted in 77% of seed germination. The in vitro environment was significantly superior to the ex vitro environment.

ABSTRACT. Olive trees have been grown since the beginning of civilization, and the consumption of olives and olive products is increasing worldwide, due to their health benefits and organoleptic qualities. To meet the growing market for olives, commercial cultivation of this species is expanding from traditional areas to new regions. Although the Brazilian olive industry has just begun to be established, breeding programs are already developing cultivars that are more adapted to local conditions. We used 12 microsatellite markers to evaluate 60 olive accessions, including several cultivars that were developed in Brazil. The analyses identified 72 distinct alleles; the largest number of alleles per locus were at the markers Genetic diversity in olive germplasms GAPU 101 and GAPU 71B, which contained 10 and 9 alleles, respectively. The largest allelic diversity and polymorphic information contents were also found at the GAPU 101 and GAPU 71B markers, with values of 0.8399/0.8203 and 0.8117/0.7863, respectively. Additionally, the 12 microsatellite markers generated a cumulative identity probability of 1.51 x 10 -10 , indicating a high level of accuracy of accession identification. The set of markers that we used allowed the identification of 52 of the 60 olive genotypes, in addition to the recognition of several varietal synonyms. The components of a two-dimensional principal coordinate analysis explained 48.6% of the total genetic variation. The results obtained from the microsatellite markers showed a substantial degree of genetic diversity in the olive tree accessions used in Brazil.

Morphological and agronomical describers are traditionally used in plant characterization. However, the usage of these describers have some limitations such as susceptibility to abiotic and biotic stress and environmental factors. Furthermore, the describers are not stable over time and many can only be evaluated during the adult phase of the plants, which requires time and physical space. Molecular markers offer numerous advantages compared to the conventional alternatives based on phenotype: they are stable and detectable in all vegetable tissues, and are independent of the environment and development phase. One of the main advantages of the use of molecular markers is the time reduction in the identification of genetic diversity among the studied subjects, as the genotypes may even be described for the seed or seedling phase. Many countries have already adopted molecular markers to identify olive cultivars more accurately. The aim of this study was to evaluate the genetic identity of eight olive accessions supposedly belonging to cultivar Arbequina by using microsatellite (SSR) and Sequence Characterized Amplified Region (SCAR) markers. One accession corresponding to the cultivar was also incorporated into the analysis as a reference genotype. The molecular marker data were analyzed on the software GENALEX6. The markers generated an accumulated PI and PE of 1.26 x 10-6 and 0.949, respectively. The results supported the hypothesis that all accessions belong to the cultivar Arbequina, and the markers can therefore be applied to other varieties of olive species.

This study aimed to identify and quantify the weed species in an area of organic acerola cultivation in the Distrito de Irrigação dos Tabuleiros Litorâneos do Piauí (DITALPI) in Parnaíba, Piauí, Brazil. Phytosociological sampling was completed in the rainy season, before the farmers adopted management techniques for the plants. Thirty plots of 0.25 m2 were sampled. The plots were located between crop rows, which consisted of herbaceous-subshrub plants. The absolute and relative covers and the absolute and relative frequencies of each species were calculated based on the occurrence and cover of each species. In total, 25 species comprising 13 families were registered, among which the Poaceae family that presented the largest number of species. Commelina benghalensis occurred the most frequently overall. Shannon’s diversity index (H’) and evenness were calculated as 2.30 nats ind-1 and 0.69, respectively. Five species accounted for 79.33% of absolute cover at DITALPI. The species were distributed heterogeneously within the field, and Commelina benghalensis, Urochloa plantaginea, Panicum maximum, Amaranthus spinosus, Cynodonsp., and Cyperus aggregatus were the species most likely to infest the acerola crop. As DITALPI is an area of organic cultivation, understanding these species is essential to help farmers select the best form of control.

Resultados de pesquisas confirmaram os atributos medicinais da erva baleeira (Varronia curassavica Jaqc), uma espécie que apresenta metabólicos com propriedades anti-inflamatória e analgésica e que está incluída na lista oficial de plantas medicinais de valor reconhecido pelo Ministério da Saúde brasileiro. Esses constituintes estão presentes nas folhas e ramos que são usados no preparo de chás ou utilizados pela indústria para extração do óleo essencial. O objetivo desse estudo foi caracterizar o crescimento e produção de óleo da espécie nas condições de Parnaíba, Piauí, Brasil. No ensaio, foi adotado o delineamento inteiramente casualizado, com seis tratamentos, constituídos de espécimes oriundas de matrizes cultivadas em seis talhões de um plantio, quatro repetições e quatro plantas por tratamento. Avaliou-se número de inflorescências aos trinta dias após o plantio, início da frutificação, altura total, diâmetro do colo, número de plantas vivas e produção de óleo essencial. Os dados obtidos foram submetidos à análise de variância e as médias comparadas por Teste de Tukey, no nível de significância de 5%. Após um ano, foram verificadas poucas flores aos trinta dias após o plantio, frutos maduros aos noventas dias de plantadas e altura média de 80,2 cm. Através das três extrações realizadas obteve-se uma produção média de 0,72 mL de óleo a partir de 500 g de folhas frescas. Houve diferenças significativas nas quantidades obtidas nas diferentes extrações. O crescimento e a produção foram influenciados por nematoides de galhas, que promoveram a morte da maioria das plantas e diminuição na quantidade de óleo extraído.